1. Field of the Invention
The present invention relates to an improvement in the assembly operation, a reduction in the cost of and an improvement in the environmental issue of an air conditioner.
2. Discussion of the Background
In FIG. 24 is shown a part of a conventional air conditioner, which includes a drain pan having a hollow space therein for thermal insulation, and which has been disclosed in JP-A-611148 for instance. The conventional air conditioner decreases the amount of a thermal insulation material to reduce fabrication steps, and the drain pan 24 is prepared so as to include an outer layer 25 made of ABS resin and the hollow space 26 formed therein by known gas injection molding.
The function of the drain pan will be explained as follows. In general, the inner side 28 of the drain pan 24 has the tendency to have a lower surface temperature than the outer side 27 since the inner side is close to a heat exchanger and contacts cooled droplets. However, the gas in the hollow space 26 inside the outer layer 25 has a superior thermal insulation property. Even if there is a temperature difference between the inner side 28 and the outer side 27, the gas in the hollow space 26 shuts off the heat transfer therebetween. By this arrangement, the air close to the outer side 27 is not noticeably cooled and vapor condensation is not provided on the outer side 27.
In FIG. 25 is shown a conventional plug arrangement for an air conditioner drain pipe, which has been disclosed in JP-A-58-33980 for instance, which is shown in exploded fashion. In this Figure, reference numeral 101 designates a drain pan, reference numeral 102 designates a drain pipe, which is connected to the drain pan so as to pass therethrough, and reference numeral 103 designates a blind plug to be mounted to the drain pipe for clogging the drain pipe.
The function of the blind plug will be explained as follows. Referring to FIG. 25, the drain pipe 102 is inserted in the drain pan 101 to be engaged therewith, and the blind plug 103 is forcibly capped on the drain pipe 102 to be engaged therewith.
In FIG. 26 is shown an exploded perspective view of essential portions of another conventional plug arrangement for a drain pipe, in FIG. 27 is shown a cross-sectional view to explain how a drain pipe joint is mounted, in FIG. 28 is shown a perspective view of the rain pipe joint, and in FIG. 29 is shown cross-sectional view to explain how a blind plug is mounted. In FIG. 30 is shown a perspective view of the blind plug. In these Figures, reference numeral 101 designates a drain pan, reference numeral 102 designates a drain pipe joint, which passes through and is engaged with a hole 101a formed in the drain pan 101, reference numeral 102a designates a flange of the drain pipe joint 102, reference numeral 102b designates the tubular body of the drain pipe joint 101, reference numeral 102c designates a stopper, which is provided on an end of the tubular body of the joint and has a leading edge provided with a conical portion, and reference numeral 102d designates a through hole in the drain pipe joint.
If the drain pipe joint 102 is not needed, the blind plug 103 is inserted into the hole 101a in the drain pan 101 to be engaged therewith as shown in FIG. 29. If the joint is needed, the joint 102 is inserted into the hole 101a in the drain pan 101 to be engaged therewith as shown in FIG. 27. A hose 104 for leading drain water to outside is engaged with the joint 102 as shown in FIG. 31 to drain the water from the drain pan to outside through the through hole in the joint 102 and the hose.
The drainage for a drain pan thus prepared is used in an air conditioner as in the fashion shown in FIG. 32.
Since the conventional drainage is thus constructed, the blind plug and the joint must be exchanged as required, which takes some time to exchange the parts, or which means that the plural parts are required to be ready all the time, that is wasteful.
Since the conventional air conditioner is configured to be provided with the hollow space by gas injection, the air layer can not be provided so as to have a certain thickness or a greater thickness which means that a great deal of thermal insulation cannot be provided. Costs, such as a molding cost, are required.
From the viewpoint that the environmental issue has been presently discussed, it is recommended that used parts can be easily separated according to type. When an insulation material or a similar member is provided on a lower side of a heat exchanger to prevent secondary air from being sucked, there has been created a problem in that separation of the insulating material for disposal is troublesome.